package moudle;


import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class DBUtil {
    private  volatile static DataSource dataSource=null;

    private static DataSource getDataSource(){
        if(dataSource==null){//避免过多的加锁操作
            synchronized (DBUtil.class){
                if(dataSource==null){
                    dataSource=new MysqlDataSource ();
                    ((MysqlDataSource)dataSource).setUrl ("jdbc:mysql://127.0.0.1:3306/blog_system?characterEncoding=utf8&useSSL=false");
                    ((MysqlDataSource)dataSource).setUser ("root");
                    ((MysqlDataSource)dataSource).setPassword ("88888888");
                }
            }
        }
        return dataSource;
    }

    public static Connection getConnection() throws SQLException {
        return getDataSource ().getConnection ();
    }

    public static void close(Connection connection, PreparedStatement statement, ResultSet resultSet) {
        if (resultSet != null) {
            try {
                resultSet.close ();
            } catch (SQLException e) {
                throw new RuntimeException (e);
            }
        }
        if (statement != null) {
            try {
                statement.close ();
            } catch (SQLException e) {
                throw new RuntimeException (e);
            }
        }
        if (connection != null) {
            try {
                connection.close ();
            } catch (SQLException e) {
                throw new RuntimeException (e);
            }
        }
    }

}
